Lens barrel

Abstract

The present invention provides a lens barrel comprising: a first focus ring which is used for either one of instruction types of focus operation of a relative position instruction type focus operation for moving a position of the focus lens for focus control with respect to an optical axis direction in a relative positional relation to a rotation position of the focus ring and an absolute position instruction type focus operation for moving it in an absolute positional relation; a second focus ring which is used for the focus operation of the instruction type different from that of the first focus ring between the relative position instruction type focus operation and the absolute position instruction type focus operation; a support device which slidably supports the first focus ring in the optical axis direction; a connecting device which brings the first focus ring and the second focus ring from an unconnected state into a connected state when the first focus ring slidably supported by the support device is slid from a first position to a second position; and a cover member covering the outer circumference portion of the second focus ring.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a lens barrel and particularly to a lens barrel provided with a focus ring for focusing operation and a mechanism for driving the focus lens by a motor according to a rotation position of the focus ring by electrically detecting the rotation position of the focus ring. [0003] 2. Description of the Related Art [0004] A consumer video camera in general has an automatic focus function so that focusing can be controlled by switching between automatic focus and manual focus. Thus, a lens for focus control (focus lens) is driven by a motor, and a manual focus is carried out by electrically detecting the rotation position of a focus ring provided rotatably at a lens barrel by a position sensor, for example, and by moving the focus lens by the motor according to the detected rotation position. And the focus ring and the focus lens are so constructed that they are not mechanically interlocked...

AI Technical Summary

Benefits of technology

[0008] Then, as a measure considering the operability of focus when a video camera is used as consumer use and the operability of focus when the video camera is used for broadcasting, two focus rings of the relative position instruction type and the absolute position instruction type are provided at a lens barrel so that the focus rings can be used according to preference or the like of users. According to this idea, users who mainly use automatic focus and users who use the manual focus as a correcting device for focus control by the automatic focus can now use the relative position instruction type focus ring, while users who mainly use the manual focus (professional photographers and the like) can use the absolute position instruction type focus ring, which realizes favorable focus operation for any user.

[0010] The present invention has been made in view of the above circumstances and has an object to provide a lens barrel which can prevent nonconformity to erroneously operate an instruction type focus ring not intended to be operated by the user when a relative position instruction type and an absolute position instruction type focus rings are provided at a lens barrel.

[0012] According to the present invention, when the relative position instruction type and the absolute position instruction type focus rings are arranged on the barrel body, the first focus ring can be switched to a state of connection or disconnection with the second focus ring by sliding the first focus ring used for one of the instruction types. Therefore, the second focus ring can be rotationally operated by the first focus ring, and there is no need of rotational operation by directly touching the second focus ring. Then, by covering the second focus ring by the cover member, nonconformity of erroneous operation of the focus ring of the instruction type not intended to be operated by the operator can be prevented.

[0014] According to the present invention, it is effective to use the first focus ring which is slidable and operated through direct touch by the operator for the relative position instruction type focus operation and to apply the indication of the photographing distance usually marked on the absolute position instruction type focus ring to the second focus ring when the second focus ring covered by the cover member for the absolute position instruction type focus operation is used, and in that case, the opening is formed on the cover member to prevent inability to visually check the indication due to the cover member.

[0017] According to the lens barrel of the present invention, when the two focus rings of the relative position instruction type and the absolute position instruction type are provided at the lens barrel, the nonconformity that the user erroneously operates the focus ring of the instruction type not intended to be operated can be prevented.

Problems solved by technology

When these professional photographers use the above relative position instructing type focus ring, they can not recognize that the focus lens has reached the close-up end or infinite end by the operation feeling of the focus ring, and there is nonconformity that the operability is poor.

However, if there are different instruction types of focus rings in one lens barrel, there is a fear of wrong operation of an instruction type focus ring not intended to be operated by the user taken it as the other focus ring or unintentional touching and moving of it.

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